starr



Unteren STATES PATENT @Erica ELI T. STARR, OF PHILADELPHIA, PA.,ASSIGNOR T() JAMES W. WHITE, J. CLARENCE WHITE, AND H. M. LEWIS,TRUSTEES, OF SAME PLAGE.

HAND TOOL. OR IMPLEMENT.

SPECIFICATION forming part of Letters Patent No. 237,062, dated January25, 1881.

Application filed July 16, 1880.

To all whom it may concern:

Be it known that I, ELI T. STARR, a citizen of the United States,residing in the city and county of Philadelphia, in the State ofPennsylvania, have invented certain new and useful Improvements in HandTools or Implements, of which the following is a specification.

My invention relates to the class of handinstruments in which a socketedhandle is employed for the reception of the shank of an operating-tool,so that the handle may be a common one to several tools which arecapable of being easily inserted, securely held, and readily removedfrom the handle.

The object of my invention is to provide an instrument of the type abovereferred to which is capable of a high nish, is capable of convenientmanipulation with a firm grasp Without unduly fatiguing the hand, isreliable in its operation, and is withal comparatively in expensive,while permitting the ready change of the operating-tools, as desired.

The subject-matter claimed is particularly pointed ont at the close ofthe specification.

The accompanying drawings illustrate the best Way now known to me ofembodying my improvements.

In said drawings, Figure l is an enlarged view of the improvedinstrument complet-e; and Fig. 2 is a sectional View, on a scale stilllarger than that depicted in Fig. l, of the front end of the handle,with an operating-tool inserted therein constructed according to myinventiom,

The handle A is preferably made of metal, highly finished in ways wellknown in the art, with a preferably roughened surface, to afford a firmgrasp without unduly fatiguin g the hand in operation. Thefront end ofsaid handle Ais socketed for the reception of an operating-tool, thesocket preferably consisting of a smooth I front portion, a, ascrew-threaded portion, a',

in rear of said smooth portion, and a conical or tapering seat ortermination, a2. (See Fig.

2.) The socket may consist of the threaded portion and the tapering orconicalseat only; but I prefer the form of socket first described.

The operating-tool B has a shank formed correspondently with the socketof the handle (No model.)

A, so as to lit said socketthat is, the said tool has a round orcylindrical portion, b, to iit the corresponding front smooth bore orportion, a, of the socket. It has a screw-threaded portion, b', to itthe female screw a of said socket, and it has a conical or tapering end,b2, which fits the corresponding seat a2, constituting the terminationof the handle-socket. The shank of the tool may have the screwthreadsand tapering end or termination only to t a corresponding socket; but Iprefer the form of tool-shank first described. The object in having theround portion b of the toolshank B to fit the similar portion of thesocket in the handle A is to give the tool a long bearing in the handleat front, to secure steadiness firmness, and rigidity of the tool. Theobject in providing the shank with screw-threads is to secure the toolrmly in the handle from endwise movement and to take up wear, Whilepermitting of the ready change of tools; and the object in having thetapering or conical end of the tool to t a corresponding seat in thehandle is to produce friction sufficient to prevent the tool fromturning or unscrewing during the ordinary'use of the instrument.

I have shown my improvements organized as a dental plugging-instrument,which is to be used in the same manner as the ordinary hand-pressureplugging-tools which my iinproved instrument is intended to supersede.

My improvements may also be organized as chisels, excavators, 85e.,suoli as used by dentists.

The dentist, in illin g, plugging, or working upon teeth, requires anumber of tools or points with ends varying in shape and construction toreach different parts ofthe cavity in the tooth,for operation indifferent positions in the mouth, and for operation upon llings andteeth of diiferent characters. The importance and advantages of myimprovements are therefore obvious.

The taper given to the end of the tool and to the seat in the handlewhich it occupies, may, of course, be varied according to the amount offriction desired, while I also contemplate constructing the handles ofdifferent sizes adapted to tools of a uniform size of shank, or to toolsor points the shanks of which are adapted only to the particular sizedhandle with which they are to be used.

I am aware that screW-shanked operatingtools have been used having acylindrical portion in front provided with a bolster or enlargement toabut against the front end ofthe handle in which they lit. My tool hasno such bolster, as a bolster on thc tool abutting against the front endof the handle would prevent adjustment to compensate for Wear of thescrew and tapering end ofthe tool, and of the handle-socket, as shown byme.

I claim as my invention- 1. The operating-tool constructed, substantially as hereinbet'ore set forth, with a shank having a. plainunbolstered cylindrical portion, a screw-threaded portion in rear ofsaid c vlindrical portion, and a lengthened tapering buttl end ortermination. l

2. The combination, substantially as herein before set forth, of theinstrument-handle having a socket consisting of a smooth front portion,a screw-threaded portion, and an extended tapering portion constitutingthe termination of said socket, with a tool fitting said sockethavingaround unbolstered or plain shank, a screw-threaded portion, andan extended tapering end or termination, whereby the tool is firmlylocked in the handle during use, is readily removable to permit changeot' tools, and may be adjusted in the handle to compensate for wear andinsure a firm connection.

1u testimony I have hereunto subscribed my name.

ELI T. STARR.

Witnesses:

WM. J. PEYTON, L. B. WIGHT.

